Commercial aircraft, such as the Airbus A320 or Boeing 737, are typically constructed from modular components, the size, weight and construction of which are dictated by many considerations, including fuselage dimensions, aesthetic and safety. Many of these requirements are imposed by law or regulation. Aircraft components, such as overhead stowage compartments, seats, lavatories, galleys, lighting systems, etc. are all required to function within strictly confined spaces.
Manufacturers of aircraft are constantly refining interior aircraft designs to achieve more comfort and utility for passengers and crew within carrier-imposed restraints on cost, weight, maintenance down-time, and safety. Commercial passenger aircraft generally include lavatories for use by passengers and crew that include a toilet therein. Cleaning of and replacement of the toilet can often prove difficult.